Turbine generator installation



June 28, 1932. o. JUNGGREN 1,855,258

U TURBINE GENERATQR INSTALLATION Filed June 20, 1929 2 Sheets-Sheet l Inventor: Oscar Jur ggren, 19g 0% His Attorngg.

June 28, 1932. o. JUNGGREN 1,865,258

TURBINE GENERATOR INSTALLATION Filed June 20, 1929 2 Sheets-Sheet 2 nventor C] 5 car Junggren,

@ Wf/m His Attorngg.

Patented June 28, 1932 UNITED STATES PATENT OFFICE OSCAR JUNGGREN, OF SCHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK TURBINE GENERATOR INSTALLATION Application filed June 20,

At the present time the users of turbine generators demand that such apparatus be capable of delivering very large amounts of power. In most of the modern power plants the floor space available for such apparatus is greatly restricted. To meet this condition I propose to divide the turbine apparatus into two principal parts or portions, one part operating with high pressure motive fluid and the other with low pressure fluid exhausting from the first, and, in order to save floor space, to mount the high pressure part or portion above the other. lVhile this may seem to be a relatively simple thing, as a matter of fact it involves very serious problems due to the fact that the parts of the turbine operate at greatly different temperatures which give rise to unequal expansions of the metal parts, to the great weights involved and also to the relatively high speeds of the apparatus. It is also complicated by the fact that the generators do not have the same ratios of expansion as do the turbine parts. As an illustration of the great weights involved I may refer to an installation of 110,000 kilowatts capacity of my design. In this case the low pressure part, unit or element weighs approximately 790,000 pounds, and the high pressure part, unit or element, which is mounted thereon, weighs approximately 256,000 pounds. In such an installation each turbine part or unit must be permitted to expand and contract longitudinally with temperature changes without affecting the other part or unit, and said turbine parts must be permitted to independently expand and contract in a radial direction. The longitudinal movements of the high pressure unit are comparatively large while the radial movements are small, being in the order of a few thousandths of an inch.

The low pressure unit being much wider in proportion to its length will expand more uniformly. In general, expansions due to heat are taken up by sliding, keys being used to maintain original alignment and this arrangement can be used for the lateral expansion between bridge and exhaust casing instead of the one above described.

As above stated, the parts of the two gen- 1929. Serial No. 372,265.

erators also expand and contract, but to a much lesser degree.

My invention has for its object to provide an improved mounting for turbine installations of the character described in which the parts are not only securely mounted one above the other but also have means whereby the independent movements due to temperature changes of the several parts constituting the assemblage are suitably provided for.

For a consideration of what I beleive to be novel and my invention, attention is directed to the accompanying description and the claims appended thereto.

In the drawings, which are illustrative of my invention, Fig. 1 is a view partly in section and partly in side elevation of a turbine generator installation; Fig. 2 is an end view of the frame which supports the generator bearing; Fig. 3 is an end view of the structure shown in Fig. 1 with certain of the parts in section, and Fig. l is a slight modification of the bridge members which support the high pressure turbine element.

5 indicates the foundation plates which are securely anchored to the concrete or other foundation for the turbine installation. Mounted on these plates are laterally extending feet 6 which are formed as integral parts of the lower half of the casing of the low pressure unit. To fix the turbine in place on the foundation, a cross key 7 is provided. In most cases it will be desirable to use two such keys and aline them endwise. From these keys the turbine casing is free to expand and contract axially due to heat changes. The ends of the casing are provided with axially extending keys 8 which guide the axial movements of the casing due to expansion and contraction.

9 indicates the upper half of the casing of the low pressure unit or element and which is made in a suitable number of parts as is usual in such constructions. Along its lower edges are formed outturned flanges 10, Fig. 3, which rest on the feet 6 of the lower half of the casing. The side portions of the easing are also provided with shoulders 11 upon which the structure supporting the high pres sure element rests.

The rotor may be of any suitable construction and operate on the impulse or reaction principle or a combination of both. As shown, it operates on the impulse principle. It comprises a shaft 15 upon which are mounted numerous rows of moving buckets 13 with rows of stationary guide blades or nozzles 14 between. The shaft 15 of the rotor is carried at its ends in bearings 16 which are supported by the casing of the element. It is important that the casing and bearings have the same supporting means so that the expansion and contraction of the metal will affect all parts as nearly equally as possible. It is also for this reason that the casing is supported as nearly as possible in the horizontal plane of the shaft to permit of free radial expansion and contraction. Below the casing are conduits 17. which convey exhaust steam to the condenser 18. Steam is admitted at the center of the turbine casing by the conduit 19. It may be received directly or indirectly .fromthe high pressure unit. Steam on entering the turbine flows left and right through the nozzles and buckets to the exhaust housings of the casing and thence by conduits 17 to the condenser. Such an arrangement is advantageous because very large volumes of steam may be handled without making the rotor diameter excessively large.

Referring now to the high pressure unit and to the means for supporting it, two bridge members 20 and 21 extending cross-wise or transversely of the assembly are provided, each of which forms an arch with its lower edges resting on the shoulders 11 of the casing of the low pressure unit. These bridges should be made sufficiently strong to support their load without spreading or deflecting at the bottom and are provided with flat top surfaces which support'the high pressure unit. The lateral difference of expansion between the bridges supporting the high pressure unit and the low pressure exhaust casing is taken up by elastic deformation of both bridges and the low pressure exhaust casing. As it is impossible to predict with any certainty what the natural period of vibration of these bridges may be, and since it is highly undesirable that they should have the same period of vibration as either of the turbine elements, means are provided whereby its or their periods of vibration may be changed. To this end one or both of the bridges is or are provided with heavy longitudinal ribs 22 and cross ribs 23 which have enlarged lower ends. In the pockets thus formed concrete or other heavy material 24;, Fig. 3, may be inserted and by means of which the mass and therefore the period of vibration of the bridge may be changed without in any way changing the turbine elements.

As shown in Fig. 3, the bridges are in the form of separate castings but if desired they may, where the conditions are otherwise satisfactory, be made integral with certain parts of the casing of the low pressure element, for example as a part of the exhaust housings as shown in Fig. 4. In both cases the weight of the bridges and their load are supported by the feet 6 of the casing of the low pressure element which in turn are supported by the foundation plates. The casing of the low pressure H element will ordinarily be lagged with suitable heat insulating material. Between the casing and the under surface of the bridge members are spaces 24 through which air may be circulated for ventilating purpose. This is facilitated by providing openings 25 in the walls of the bridges.

The high pressure turbine element is made in the form of a longitudinal bridge, the ends of which rest on the cross-wise bridges. The upper surface of the bridge 21 has a fiat, horizontal platform upon which the exhaust end of the turbine element rests. Between the two parts is a cross-key 26 which anchors the element against longitudinal movement at this point, it being free to move toward the left as the temperature rises and the casing expands. To guide the front or inlet end of the element, the bridge 20 is made flat on the top and is provided with a pair of guides 27 between which is located the pillow block or element 28 which carries the main front bearing and also the front end of the casing. In the pillow block are recesses 29, Fig. 1, in which are located a pair of arms or extensions 29a formed integral with the lower half of the casing. These arms are connected to the block by cross-keys 30 which cause it to move to and fro with the casing as it expands and contracts and which also permits the casing and the arms or extensions to move radially in a horizontalplane to compensate for radial expansion of the turbine casing. The turbine casing and pillow block are also united by an axial key to ensure equal movements of the arms from and toward the axis of the machine.

The exhaust end of the turbine element is provided with a bearing 31 which is suitably supported on the pillow block which is anchored by the cross-key 26. Beyond the bearing is a relatively long coupling 32 of any suitable construction which compensates for any small lack of alignment of the turbine and generator shafts. In order to restrict the lack of vertical alignment due to te1nperature variations to a negligible amount the generator bearing 33 is mounted in a frame 3e which is also supported by the feet of the low pressure turbine element. This frame is what is known as an A-frame and is made hollow. In order that its temperature and therefore its expansions an'dcontractions shall closely correspond to those of the turbine, the interior -of the frame is placed in communication with the exhaust housing of the low pressure element by the conduit 35. The upper end of the frame is also connected rigidly to the bridge member 21 by one or more studs 36.

Steam is admitted to the high pressure element from the supply chest subject to the control of one or more valves 87 and after flowing through the stationary and rotating parts of the turbine exhausts through conduits 38, one on each side, and enters the low pressure element by conduits l9 of which there are two, one on each side. 39 indicates a conduit by means of which steam can be extracted from an intermediate for any de sired purpose.

In general it may be stated that the turbine for the high pressure element may be of any suitable type or construction, the one shown as being of the multi-stage impulse type.

40 indicates the electric generator which is driven by the low pressure element, and ll the generator driven by the high pressure element said generators being mounted one above the other and enclosed in the same or separate casing. Usually these generators will be of the alternating current type and connected for parallel operation.

.What I claim as new and desire to secure by Letters Patent of the United States is:

1. In a turbine installation, the combination of a low pressure unit having a casing with horizontal shoulders, a pair of arched members each of which extends across said unit, encloses the upper part of the casing in spaced relation thereto and is supported at its lower ed 'es by said shoulders, a high pressure unit which is supported near its ends on the arched members, a means carried by one of the arched members for anchoring the high pressure unit at one end against axial movement, and a means carried by the other arched member which permits of the other end of said unit to freely move in a longitudinal direction due to temperature changes.

2. In a turbine installation, the combination of a low pressure unit having a casing with horizontal flanges and shoulders, a foundation therefor upon which the flanges rest, means for anchoring the unit to the foundation at one point while permitting it to expand axially and radially at all other points, a removable arched member which spans said unit in spaced relation thereto in its central part and is supported by the shoulders of the unit at its lower edges, a second arched removable supporting member located above the unit in spaced relation thereto and supported by the shoulders, a high pressure unit which is supported near its ends by the two members, means for anchoring the unit to one of the members while permitting it to expand axially and radially at all other points, and means carried by the other member for guiding the unit in its axial movements.

3. In a turbine installation, the combination of a low pressure unit having a casing, an apparatus driven thereby, arched members arranged in spaced relation to the unit and extending cross-wise thereof and supported at their lower edges by said unit, a high pressure unit supported on top of the arched members, an apparatus driven thereby, a bearing for the shaft of the last named apparatus which shaft is driven by the high pressure unit, and a frame supported upon the feet of the casing of the low pressure unit, which carries the said bearing.

4:. In a turbine installation, the combination of a low pressure unit having a central inlet and exhaust housings, a pair of transverse arched members, each of which encloses the upper part of an exhaust housing and in spaced relation thereto, the lower edges of the members resting on the low pressure unit, a high pressure unit which is supported by the tops of thepair of arched members, and means for anchoring the high pressure unit on one of the arched members and permitting it to slide on the other.

5. In a turbine installation, the combination of a low pressure unit having a casing, a pair of removable arched members which extend cross-wise thereof and in spaced relation thereto and which are supported at their lower edges by the casing of the unit, means associated with one of the members to receive additional material to change its natural period of vibration, and a high pressure unit which is supported by the tops of the pair of arched members.

6. In a turbine installation, the combination of a low pressure unit having a casing, an apparatus driven thereby, a transversely extending arched member arranged in spaced relation to the unit and supported thereby, a second arched supporting member parallel to the first and supported by the casing of the unit, a high pressure unit which is wholly supported by the members, an apparatus driven thereby and located directly over the other apparatus, a bearing for one end of the shaft of the last named apparatus, a hollow frame which supports the bearing and in turn is supported by the casing, and conduit means connecting the interior of the frame and to the exhaust of the low pressure unit so that changes of temperature within the unit produce corresponding changes within the frame.

7. In a turbine installation, the combina tion of a low pressure unit, a high pressure unit mounted in the same vertical plane as the axis of the low pressure unit, one above the other, a pair of spaced transversely extending supporting members for the high pressure unit, the weight of which and that of the high pressure unit being carried by the low pressure unit, said members being in spaced relation axially with respect to each other and radially with respect to the low pressure unit, and anchoring means for each unit which holds one part thereof against axial movement while permitting the other part thereof to move freely due to temperature changes, the anchoring means for one of the units being carried by one of the transversely extending members.

8. In a turbine installation, the combination of a low pressure unit having a casing, a pair of arched members, each of which encloses the upper part only of the unit in spaced relation thereto, extends cross-wise thereof, is supported at its lower edges by the casing of said unit and has a flat upper surface, and a high pressure unit which is supported near its ends by the fiat surfaces of the arched members.

9. In a turbine installation, the combination of a low pressure unit having a casing divided horizontally in the plane of its axis and provided with shoulders adjacent the plane of division, a pair of arched members which extend cross-wise of the casing, vare separated therefrom by a space and are supported at their bottom edges by the shoulders of the casing, and a high pressure unit which is directly over the low pressure unit, is supported at its ends by the arched members and supplies elastic fluid to the low pressure unit.

In witness whereof, I have hereunto set my hand this 18th day of June, 1929.

OSCAR JUNGGREN. 

